Optimal heating conditions for forming a mouthguard using a circle tray: Effect of different conditions on the thickness and fit of formed mouthguards

Abstract

Within the limitation of this study, it was suggested that when forming a mouthguard using a 4.0-mm EVA sheet and a circle tray on a vacuum forming machine, the sheet should be formed at a sagging distance of 10-mm.

Influence of continuous use of a vacuum‐forming machine for mouthguard thickness after thermoforming

“…The timing for forming is conventionally judged by the sagging distance, the sheet's softening temperature or the heating time. [13][14][15][16][17] Forming machines have either a single-sided or double sided heating mechanism. 15 Judging the timing from the sagging distance is simple, so it is used for many vacuum-forming machines.…”

“…This timing is often recommended by the manufacturer because it is specific to the machine and to the thickness and material of the sheet. 15,[17][18][19] The temperature was constantly higher on the heated surface than on the non-heated surface. [13][14][15][16][17] Forming machines have either a single-sided or double sided heating mechanism.…”

“…It is therefore crucial to determine the molding timing based on when the sheet temperature of the non-heated surface pressed against the model reaches an appropriate softening temperature. The correct timing for both materials is indicated by a sag of 15 mm for a 4.0-mm-thick sheet 17,21. The correct timing for both materials is indicated by a sag of 15 mm for a 4.0-mm-thick sheet 17,21.…”

“…Results of one-way ANOVA for thickness after formation, (a) ethylene vinyl acetate, (b) olefin copolymer molding can result in a poor fit 15,[17][18][19]. It is therefore crucial to determine the molding timing based on when the sheet temperature of the non-heated surface pressed against the model reaches an appropriate softening temperature.…”

“…The temperature of the nonheated surface was 80°C or more (ie, the correct timing of the forming) which corresponds to the control,17,21 and the sheet temperature of each point of AF10 was about the same as the control. Hence, it can be inferred that the softening states of both are similar.…”